I doubt whether he will come.

我怀疑他是否会来。

youdao

I doubt whether he will succeed.

我怀疑他是否会成功。

youdao

I doubt whether it is true.

我怀疑这是不是真的。

youdao

However, I doubt whether such ideas will cut much ice with the closet elitists.

BBC: Staying-on: Is it a good idea?

Speaking as one who lived in Asia for a decade, I doubt whether these values are held as strongly outside the U.S. and (to a lesser extent) Europe.

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"I doubt whether we should have a system whereby the quality of the bar drives student choice and student choice drives the survival of our institutions in higher education, " she said.

BBC: Reforms 'could cause some universities to fail'